Depending on the requirements of your projects, a different architectural approach will be needed. To make the right decisions when designing your solutions, it is important to understand the services and AIF architecture.

Compared to Microsoft Dynamics AX 2009, there have been a lot of improvements made to the service architecture in Microsoft Dynamics AX 2012. The biggest improvement is the native Windows Communications Foundation (WCF) support. As a result, the proprietary Microsoft Message Queuing (MSMQ) and BizTalk adapters that were available in Microsoft Dynamics AX 2009 have been deprecated and replaced by adapters that use WCF. The MSMQ adapter in particular is replaced by an adapter that uses the WCF NetMsmq binding. The filesystem adapter remains intact and still allows you to import and export messages from and to the filesystem.

All services are WCF services and are hosted on the AOS. When an application wants to consume these services on the local network, no further deployment is needed because it can connect directly to the AOS. Just like with Microsoft Dynamics AX 2009, deployment on Internet Information Services (IIS) is needed for consumers that are not on the intranet. However, the services themselves are no longer deployed on IIS; instead, a WCF routing service on the IIS routes everything to the AOS.

If you want to modify messages before they are received or after they are sent, you can use pipelines and transformations. Pipelines only apply to the body of a message and are handled by the request preprocessor and response postprocessor. You can use transformations to transform a complete message, including the header. This allows you to exchange messages in a non-XML format.

The following diagram depicts the architecture as it is in Microsoft Dynamics AX 2012 and clearly shows the central role of WCF:

While not displayed in the diagram, there is now load balancing support for services using Windows Server Network Load Balancing (NLB). Combined with NLB for IIS, which was already available, this enables high availability and load balancing for services.